Interactions between commensal bacteria and viral infection: insights for viral disease control in farmed animals

Viral diseases cause serious economic loss in farmed animals industry. However, the efficacy of remedies for viral infection in farmed animals is limited, and treatment strategies are generally lacking for aquatic animals. Interactions of commensal microbiota and viral infection have been studied in recent years, demonstrating a third player in the interaction between hosts and viruses. Here, we discuss recent developments in the research of interactions between commensal bacteria and viral infection,including both promotion and inhibition effect of commensal bacteria on viral pathogenesis, as well as the impact of viral infection on commensal microbiota. The antiviral effect of commensal bacteria is mostly achieved through priming or regulation of the host immune responses, involving differential microbial components and host signaling pathways, and gives rise to various antiviral probiotics. Moreover, we summarize studies related to the interaction between commensal bacteria and viral infection in farmed animals, including pigs, chickens, fish and invertebrate species. Further studies in this area will deepen our understanding of antiviral immunity of farmed animals in the context of commensal microbiota, and promote the development of novel strategies for treatment of viral diseases in farmed animals.     

高速逆流色谱法制备灵芝萜烯酮醇

本研究建立一种从灵芝子实体提取物中快速制备灵芝萜烯酮醇的方法。以沪农灵芝1号子实体为原料,经乙醇提取、D101大孔树脂富集后,再经一次正相色谱柱层析,获得富含灵芝萜烯酮醇的流分。采用高速逆流色谱法对该流分进行分离,优化分离条件,获得的最佳条件为：溶剂体系为正己烷-乙酸乙酯-甲醇-水（V/V/V/V,12:24:18:9）,流速2.0mL/min,转速900r/min,上样量500mg,一次上样可得到纯度为90.9%的灵芝萜烯酮醇52.1mg,得率达到10.4%。该方法具有操作简单、污染小、成本低、得率和纯度高的特点,是规模化制备灵芝萜烯酮醇的一种新方法。     

Potassium and phosphorus transport and signaling in plants

Nitrogen(N), potassium(K), and phosphorus(P) are essential macronutrients for plant growth and development, and their availability affects crop yield. Compared with N, the relatively low availability of K and P in soils limits crop production and thus threatens food security and agricultural sustainability. Improvement of plant nutrient utilization efficiency provides a potential route to overcome the effects of K and P deficiencies. Investigation of the molecular mechanisms underlying how plants sense, absorb, transport, and use K and P is an important prerequisite to improve crop nutrient utilization efficiency. In this review, we summarize current understanding of K and P transport and signaling in plants, mainly taking Arabidopsis thaliana and rice(Oryza sativa) as examples. We also discuss the mechanisms coordinating transport of N and K, as well as P and N.     

3例婴儿脑膜炎败血伊丽莎白菌脑膜炎临床分析

总结脑膜炎败血伊丽莎白菌感染患儿的临床特点,以期提高临床诊治水平。收集中山市博爱医院2010年1月至2020年12月收治的3例脑膜炎败血伊丽莎白菌引起的脑膜炎患儿临床资料,结合相关文献进行总结分析。结果显示,3例患儿脑脊液中培养出脑膜炎败血伊丽莎白菌,其中2例血培养为同种细菌。3例患儿均为足月顺产,2例为新生儿期发病,1例为出生后35天发病,起病前均未发现致病高危因素。患儿以发热为主要起病表现,无抽搐及脑膜刺激征表现。3例患儿外周血常规白细胞总数、C反应蛋白、降钙素原均升高;脑脊液潘氏试验均为阳性,伴脑脊液白细胞数增高,脑脊液蛋白明显增高,脑脊液葡萄糖降低。头颅磁共振成像(magnetic resonance imaging,MRI)或电子计算机断层扫描术(computer tomography,CT)可见脑膜强化、软脑膜增厚、脑外间隙增宽,均无脑实质受累。3例检出菌株的药敏结果表现出高度一致性,均提示对环丙沙星、哌拉西林/他唑巴坦、左氧氟沙星、复方新诺明敏感。2例患儿以环丙沙星治疗,1例患儿以美罗培南联合万古霉素治疗。其中1例治愈,2例临床症状好转后出院。经电话随访,3例患儿一般情况尚可,无生长发育异常。本病例报道提示,脑膜炎败血伊丽莎白菌脑膜炎主要见于新生儿期,以发热起病为主要表现,该菌对儿科常用抗菌药物多显示体外耐药,对喹诺酮类药物敏感。     

Genomes of 12 fig wasps provide insights into the adaptation of pollinators to fig syconia

Figs and fig pollinators are one of the few classic textbook examples of obligate pollination mutualism. The specific dependence of fig pollinators on the relatively safe living environment with sufficient food sources in the enclosed fig syconia implies that they are vulnerable to habitat changes. However, there is still no extensive genomic evidence to reveal the evolutionary footprint of this long-term mutually beneficial symbiosis in fig pollinators. In fig syconia, there are also non-pollinator species. The non-pollinator species differ in their evolutionary and life histories from pollinators. We conducted comparative analyses on 11 newly sequenced fig wasp genomes and one previously published genome. The pollinators colonized the figs approximately 66.9 million years ago, consistent with the origin of host figs. Compared with nonpollinators, many more genes in pollinators were subject to relaxed selection. Seven genes were absent in pollinators in response to environmental stress and immune activation. Pollinators had more streamlined gene repertoires in the innate immune system, chemosensory toolbox, and detoxification system. Our results provide genomic evidence for the differentiation between pollinators and nonpollinators. The data suggest that owing to the long-term adaptation to the fig, some genes related to functions no longer required are absent in pollinators.     

用于白蚁防治的联苯菊酯微胶囊的制备及性能研究

针对白蚁防治药剂联苯菊酯传统加工剂型存在的安全性差、持效期短等缺点,采用溶剂蒸发法制备联苯菊酯微胶囊.通过粒径大小、外观形貌、包封率以及载药量筛选出最佳芯壁比、乳化剂用量和剪切时间,并对微胶囊理化特性及释放性能进行表征,同时考察微胶囊对白蚁的杀灭效果和持效性.研究结果表明,芯壁比为1:1.5,乳化剂用量为7％,剪切时间为6 min时制备的联苯菊酯微胶囊粒径适中(97.6μm),包封率高达70.5％,缓释性能良好,与市售乳油相比,对白蚁的杀灭效果相当,但持效性能优异.该研究获得的联苯菊酯微胶囊为安全、高效防治白蚁提供了技术手段.     

家蝇Phormicin A多克隆抗体的制备及效价检测

家蝇Phormicin作为防御素家族的成员,是一类具有广普抗菌活性的抗菌肽.本研究采用原核表达法表达并纯化获得了家蝇PhormicinA蛋白.将家蝇Phormicin A原核表达蛋白与完全佐剂和不完全佐剂乳化混匀,先后免疫新西兰白兔获得其多克隆抗体.通过原核表达蛋白中和吸附实验,以及Western blot实验验证了抗体的特异性.进一步用金黄色葡萄球菌刺激家蝇三龄幼虫样品,进行内源性验证并测定抗体的效价.结果 显示,该多克隆抗体既可以识别家蝇Phormicin A原核表达蛋白,也可以识别金黄色葡萄球菌刺激家蝇三龄幼虫产生的内源性Phormicin A蛋白.本研究为进一步探索Phormicin在家蝇天然免疫和防御中的机制等后续工作打下基础.     

杧果蔗糖合成酶MiSS基因的克隆与表达分析

为克隆杧果(Mangifera indica L.)蔗糖合成酶基因序列,预测其编码蛋白特性,阐明其在果实发育过程中的表达规律和作用.本研究采用同源克隆法和RACE技术克隆了1个编码蔗糖合成酶基因的全长cDNA,命名为MiSS,其cDNA全长2110 bp,开放阅读框为1455 bp,编码484个氨基酸,相对分子量为55.3 kD,理论等电点为6.08.系统进化分析显示,MiSS基因编码的氨基酸序列与温州蜜柑(Citrus unshiu)、荔枝(Litchi chinensis)、龙眼(Dimocarpus longan)氨基酸序列一致性为90％～93％.RT-qPCR分析显示,MiSS基因表达量呈现先上升后下降的趋势,且果实发育各时期果皮内MiSS基因表达量均显著高于果肉,综合分析MiSS基因可能与淀粉的合成密切相关.本研究为进一步了解MiSS基因在杧果蔗糖代谢过程中的作用以及从分子角度阐明植物生长调节剂对杧果蔗糖代谢的影响机理奠定了理论和技术基础.